Air conditioner ventilation device and air conditioner ventilation method

ABSTRACT

An outdoor-heat-exchanger ventilation channel definer defines an outdoor-heat-exchanger ventilation channel in which an outdoor heat exchanger is located. The outdoor-heat-exchanger ventilation channel definer has a first outdoor-heat-exchanger inlet, an outdoor-heat-exchanger outlet, and a second outdoor-heat-exchanger inlet. The first outdoor-heat-exchanger inlet and the outdoor-heat-exchanger outlet each are connected to an exterior space. The second outdoor-heat-exchanger inlet is connected to a target room. An outdoor fan creates an airflow in the outdoor-heat-exchanger ventilation channel. The airflow includes outdoor air in the exterior space drawn through the first outdoor-heat-exchanger inlet and indoor air in the target room drawn through the second outdoor-heat-exchanger inlet, passing through the outdoor heat exchanger, and discharged to the exterior space through the outdoor-heat-exchanger outlet.

TECHNICAL FIELD

The present disclosure relates to an air conditioner ventilation device and an air conditioner ventilation method.

BACKGROUND ART

A known air conditioner ventilation device ventilates a target room that is a room to be air-conditioned and air-conditions the target room using a refrigeration cycle, as described in Patent Literature 1. The target room is ventilated using an outdoor fan that both facilitates heat exchange by an outdoor heat exchanger that is a component of a refrigeration cycle and discharges air out of the target room.

CITATION LIST Patent Literature

Patent Literature 1: Unexamined Japanese Patent Application Publication No. 2009-79783

SUMMARY OF INVENTION Technical Problem

The above air conditioner ventilation device cannot air-condition a target room while concurrently ventilating the target room. However, ventilating the target room may degrade the temperature environment in the target room. Thus, the air conditioner ventilation device may desirably air-condition a target room while ventilating the target room.

To ventilate the target room with the air conditioner ventilation device, the device is to switch from defining an airflow channel through an indoor heat exchanger and an outdoor heat exchanger contained in a refrigeration cycle to defining an airflow channel for discharging the air out of the target room. The air conditioner ventilation device has a complex structure for this switching.

An objective of the present disclosure is to provide an air conditioner ventilation device and an air conditioner ventilation method that concurrently perform air-conditioning and ventilation of a target room to be air-conditioned without a complex structure.

Solution to Problem

In an air conditioner ventilation device according to one or more aspects of the present disclosure, one of an indoor heat exchanger and an outdoor heat exchanger is operable as an evaporator to evaporate a refrigerant, and the other of the indoor heat exchanger and the outdoor heat exchanger is operable as a condenser to condense the refrigerant. A cooperative system constitutes, together with the indoor heat exchanger and the outdoor heat exchanger, a refrigeration cycle in which the refrigerant circulates.

The indoor heat exchanger is located in an indoor-heat-exchanger ventilation channel defined by an indoor-heat-exchanger ventilation channel definer. The indoor-heat-exchanger ventilation channel definer has an indoor-heat-exchanger inlet and an indoor-heat-exchanger outlet each connected to a target room to be air-conditioned. The indoor-heat-exchanger ventilation channel connects the indoor-heat-exchanger inlet to the indoor-heat-exchanger outlet.

An indoor fan is located in the indoor-heat-exchanger ventilation channel. The indoor fan creates an airflow in the indoor-heat-exchanger ventilation channel. The airflow includes indoor air in the target room drawn through the indoor-heat-exchanger inlet, passing through the indoor heat exchanger, and discharged to the target room through the indoor-heat-exchanger outlet.

The outdoor heat exchanger is located in an outdoor-heat-exchanger ventilation channel defined by an outdoor-heat-exchanger ventilation channel definer. The outdoor-heat-exchanger ventilation channel definer has a first outdoor-heat-exchanger inlet, an outdoor-heat-exchanger outlet, and a second outdoor-heat-exchanger inlet. The first outdoor-heat-exchanger inlet and the outdoor-heat-exchanger outlet each are connected to an exterior space isolated from the target room. The second outdoor-heat-exchanger inlet is connected to the target room. The outdoor-heat-exchanger ventilation channel connects the first outdoor-heat-exchanger inlet and the second outdoor-heat-exchanger inlet to the outdoor-heat-exchanger outlet.

An outdoor fan is located in the outdoor-heat-exchanger ventilation channel. The outdoor fan creates an airflow in the outdoor-heat-exchanger ventilation channel. The airflow includes outdoor air in the exterior space drawn through the first outdoor-heat-exchanger inlet and the indoor air in the target room drawn through the second outdoor-heat-exchanger inlet. At least the outdoor air, among the drawn outdoor air and the drawn indoor air, passes through the outdoor heat exchanger. The outdoor air and the indoor air are discharged to the exterior space through the outdoor-heat-exchanger outlet.

Advantageous Effects of Invention

In the above structure, the indoor air is discharged to the exterior space through a second outdoor-heat-exchanger inlet while the indoor air is concurrently passing through the indoor heat exchanger to adjust the temperature of the indoor air. This structure can thus concurrently air-condition and ventilate a target room to be air-conditioned.

The target room can be ventilated through the second outdoor-heat-exchanger inlet in the outdoor-heat-exchanger ventilation channel definer without a complex structure.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 is a schematic diagram of an air conditioner ventilation device according to Embodiment 1 in a cooling operation;

FIG. 2 is a schematic diagram of the air conditioner ventilation device according to Embodiment 1 in a heating operation;

FIG. 3 is a schematic diagram of an air conditioner ventilation device according to Embodiment 2 in a cooling operation;

FIG. 4 is a schematic diagram of an air conditioner ventilation device according to Embodiment 3 in a cooling operation;

FIG. 5 is a schematic diagram of an air conditioner ventilation device according to Embodiment 4 in a cooling operation;

FIG. 6 is a schematic diagram of an air conditioner ventilation device according to Embodiment 5 in a cooling operation;

FIG. 7 is a schematic diagram of an air conditioner ventilation device according to Embodiment 6 in a cooling operation;

FIG. 8 is a schematic diagram of an air conditioner ventilation device according to Embodiment 7 in a cooling operation; and

FIG. 9 is a schematic diagram of an air conditioner ventilation device according to Embodiment 8 in a cooling operation.

DESCRIPTION OF EMBODIMENTS

An air conditioner ventilation device according to each of Embodiments 1 to 8 will now be described below with reference to the drawings. Throughout the drawings, the same or corresponding portions are given the same reference signs.

Embodiment 1

As shown in FIG. 1, an air conditioner ventilation device 100 according to the present embodiment includes an air conditioner 80 that air-conditions a target room RA to be air-conditioned. The air conditioner 80 includes an indoor heat exchanger 10, an outdoor heat exchanger 20, and a cooperative system 30. Either the indoor heat exchanger 10 or the outdoor heat exchanger 20 operates as an evaporator that evaporates a refrigerant, and the other operates as a condenser that condenses the refrigerant. Together with the indoor heat exchanger 10 and the outdoor heat exchanger 20, the cooperative system 30 constitutes a refrigeration cycle in which the refrigerant circulates.

The cooperative system 30 includes a compressor 31 that compresses the refrigerant, an expansion device 32 that expands the refrigerant, and a refrigerant pipe 33 in which the refrigerant flows and that forms a closed circuit connecting the indoor heat exchanger 10, the outdoor heat exchanger 20, the compressor 31, and the expansion device 32 described above. The expansion device 32 includes a capillary tube.

The cooperative system 30 also includes a four-way valve 34. The four-way valve 34 switches the flow of the refrigerant in the refrigeration cycle included in the air conditioner 80. The four-way valve 34 switching the flow of the refrigerant enables switching between a cooling operation performed by the air conditioner 80 to cool the target room RA and a heating operation performed by the air conditioner 80 to heat the target room RA. FIG. 1 illustrates the air conditioner 80 in the cooling operation.

The air conditioner 80 includes an indoor fan 40 that facilitates heat exchange between the indoor heat exchanger 10 and indoor air in the target room RA, and an outdoor fan 50 that facilitates heat exchange between the outdoor heat exchanger 20 and outdoor air in an exterior space RB. The exterior space RB is isolated from the target room RA by a building wall WL.

The air conditioner 80 includes a power circuit 60 that feeds power to the compressor 31, the indoor fan 40, and the outdoor fan 50, and a controller 70 that controls power fed from the power circuit 60 to the compressor 31, the indoor fan 40, and the outdoor fan 50 and controls switching of the four-way valve 34. The power circuit 60 and the controller 70 are mounted on a circuit board.

The air conditioner ventilation device 100 according to the present embodiment includes a housing 90 accommodating the air conditioner 80 described above. The housing 90 includes an indoor-heat-exchanger ventilation channel definer 91 defining an indoor-heat-exchanger ventilation channel S1 in which the indoor heat exchanger 10 and the indoor fan 40 are installed, and an outdoor-heat-exchanger ventilation channel definer 92 defining an outdoor-heat-exchanger ventilation channel S2 in which the outdoor heat exchanger 20 and the outdoor fan 50 are installed.

The indoor-heat-exchanger ventilation channel definer 91 has an indoor-heat-exchanger inlet 91 a and an indoor-heat-exchanger outlet 91 b, each connected to the target room RA. The indoor-heat-exchanger ventilation channel S1 connects the indoor-heat-exchanger inlet 91 a to the indoor-heat-exchanger outlet 91 b. The indoor fan 40 forms, in the indoor-heat-exchanger ventilation channel S1, an indoor airflow flowing from the indoor-heat-exchanger inlet 91 a to the indoor-heat-exchanger outlet 91 b.

The outdoor-heat-exchanger ventilation channel definer 92 has a first outdoor-heat-exchanger inlet 92 a and an outdoor-heat-exchanger outlet 92 b, each connected to the exterior space RB. The first outdoor-heat-exchanger inlet 92 a is connected to the exterior space RB through an outside-air intake duct D1. The outdoor-heat-exchanger outlet 92 b is connected to the exterior space RB through a discharge duct D2.

The outdoor-heat-exchanger ventilation channel definer 92 also has a second outdoor-heat-exchanger inlet 92 c, connected to the target room RA. The second outdoor-heat-exchanger inlet 92 c faces the interior of the target room RA.

More specifically, the second outdoor-heat-exchanger inlet 92 c is open in one of the outer surfaces of the housing 90 facing the interior of the target room RA. The outer surface with the second outdoor-heat-exchanger inlet 92 c extends in a direction crossing the outer surface in which the indoor-heat-exchanger outlet 91 b is open.

The outdoor-heat-exchanger ventilation channel S2 connects the first and second outdoor-heat-exchanger inlets 92 a and 92 c to the outdoor-heat-exchanger outlet 92 b. The outdoor fan 50 forms, in the outdoor-heat-exchanger ventilation channel S2, an outdoor airflow flowing from the first outdoor-heat-exchanger inlet 92 a to the outdoor-heat-exchanger outlet 92 b.

This operation of forming the outdoor airflow performed by the outdoor fan 50 reduces the atmospheric pressure of the area inside the outdoor-heat-exchanger ventilation channel S2 facing the second outdoor-heat-exchanger inlet 92 c to be lower than the atmospheric pressure in the target room RA. Thus, the indoor air in the target room RA is naturally drawn into the outdoor-heat-exchanger ventilation channel S2 through the second outdoor-heat-exchanger inlet 92 c, and discharged to the exterior space RB through the outdoor-heat-exchanger outlet 92 b together with the outdoor air.

The second outdoor-heat-exchanger inlet 92 c is located upstream from the outdoor heat exchanger 20 in the direction of airflow created by the outdoor fan 50. Thus, the indoor air passes through the outdoor heat exchanger 20 together with outdoor air and is discharged to the exterior space RB through the outdoor-heat-exchanger outlet 92 b.

The housing 90 includes a machine storage definer 93 that defines a machine storage S3 accommodating the compressor 31, the expansion device 32, the refrigerant pipe 33, and the four-way valve 34, and a circuit-board storage definer 94 that defines a circuit board storage S4 accommodating the power circuit 60 and the controller 70.

The machine storage S3 and the circuit board storage S4 are located between the indoor-heat-exchanger ventilation channel S1 and the outdoor-heat-exchanger ventilation channel S2. In other words, the indoor-heat-exchanger ventilation channel definer 91 and the outdoor-heat-exchanger ventilation channel definer 92 are isolated by the machine storage definer 93 and the circuit-board storage definer 94.

The operation of the air conditioner ventilation device 100 in cooling of the target room RA will now be described.

The refrigerant compressed by the compressor 31 is fed to the outdoor heat exchanger 20, serving as a condenser, to cool the target room RA. The refrigerant condensed by the outdoor heat exchanger 20 is expanded by the expansion device 32, evaporated by the indoor heat exchanger 10, serving as an evaporator, and then returned to the compressor 31. Through this refrigeration cycle, the indoor heat exchanger 10 is cooled, and the outdoor heat exchanger 20 is heated.

In this refrigeration cycle, the indoor fan 40 creates, in the indoor-heat-exchanger ventilation channel S1, an indoor airflow that passes through the indoor heat exchanger 10. More specifically, an airflow is created in the indoor-heat-exchanger ventilation channel S1 when indoor air is drawn through the indoor-heat-exchanger inlet 91 a, allowing the drawn indoor air to pass through the indoor heat exchanger 10 and to be discharged to the target room RA through the indoor-heat-exchanger outlet 91 b.

The indoor air thus exchanges heat with the indoor heat exchanger 10 to be cooled by the indoor heat exchanger 10. In other words, the target room RA is cooled.

In the above refrigeration cycle, the outdoor fan 50 creates, in the outdoor-heat-exchanger ventilation channel S2, a flow of outdoor air and indoor air passing through the outdoor heat exchanger 20. More specifically, an airflow is created in the outdoor-heat-exchanger ventilation channel S2 when the outdoor air is drawn through the first outdoor-heat-exchanger inlet 92 a and the indoor air in the target room RA is drawn through the second outdoor-heat-exchanger inlet 92 c, allowing both the drawn outdoor air and the drawn indoor air to pass through the outdoor heat exchanger 20 and to be discharged to the exterior space RB through the outdoor-heat-exchanger outlet 92 b.

The outdoor air and the indoor air thus exchange heat with the outdoor heat exchanger 20 to discharge heat from the outdoor heat exchanger 20. The indoor air has heat absorbed by the indoor heat exchanger 10 and can thus be cooler than the outdoor air. In addition to the outdoor air, the indoor air passes through the outdoor heat exchanger 20 to more efficiently discharge heat than when the outdoor air alone passes through the outdoor heat exchanger 20.

The indoor air discharged from the target room RA to the exterior space RB through the second outdoor-heat-exchanger inlet 92 c, the outdoor-heat-exchanger ventilation channel S2, and the discharge duct D2 is followed by new air other than the indoor air fed to the target room RA. The target room RA is thus ventilated. The air newly fed to the target room RA in place of the discharged indoor air may be fresh outdoor air or air in a living space other than the target room RA.

The operation of the air conditioner ventilation device 100 in heating of the target room RA will now be described with reference to FIG. 2.

As shown in FIG. 2, the refrigerant compressed by the compressor 31 is fed to the indoor heat exchanger 10, serving as a condenser, to heat the target room RA. The refrigerant condensed by the indoor heat exchanger 10 is expanded by the expansion device 32, evaporated by the outdoor heat exchanger 20, serving as an evaporator, and then returned to the compressor 31. Through this refrigeration cycle, the indoor heat exchanger 10 is heated, and the outdoor heat exchanger 20 is cooled.

In this refrigeration cycle, the indoor fan 40 creates, in the indoor-heat-exchanger ventilation channel S1, an indoor airflow that passes through the indoor heat exchanger 10. The indoor air thus exchanges heat with the indoor heat exchanger 10 to be heated by the indoor heat exchanger 10. In other words, the target room RA is heated.

In the above refrigeration cycle, the outdoor fan 50 creates, in the outdoor-heat-exchanger ventilation channel S2, a flow of outdoor air and indoor air passing through the outdoor heat exchanger 20. Thus, the target room RA is ventilated, and heat from the outdoor air and the indoor air is absorbed by the outdoor heat exchanger 20 after the outdoor heat exchanger 20 exchanges heat with the outdoor air and the indoor air.

The indoor air heated by the indoor heat exchanger 10 may be warmer than the outdoor air. In addition to the outdoor air, the indoor air passes through the outdoor heat exchanger 20 to more efficiently absorb heat than when the outdoor air alone passes through the outdoor heat exchanger 20. More specifically, the heat of indoor air can be recovered by the outdoor heat exchanger 20.

The indoor air heated by the indoor heat exchanger 10 and passing through the outdoor heat exchanger 20 can also reduce frosting on the outdoor heat exchanger 20. This will be described in more detail. An outdoor heat exchanger 20 with a known structure may greatly reduce the heat exchange efficiency when frosted due to moisture in outdoor air with low temperature and high humidity.

In the present embodiment, in addition to the outdoor air, the indoor air heated by the indoor heat exchanger 10 also passes through the outdoor heat exchanger 20 to reduce frosting on the outdoor heat exchanger 20. The outdoor heat exchanger 20, when frosted, can be defrosted by the heated indoor air. This prevents the heat exchange efficiency of the outdoor heat exchanger 20 from decreasing although the outdoor air has low temperature and high humidity.

In the present embodiment described above, while the indoor air is passing through the indoor heat exchanger 10 to adjust the temperature of the indoor air, the indoor air is also discharged through the second outdoor-heat-exchanger inlet 92 c to the exterior space. This allows concurrent air-conditioning and ventilation of the target room RA.

The target room RA is ventilated through the second outdoor-heat-exchanger inlet 92 c in the outdoor-heat-exchanger ventilation channel definer 92, without using a complex structure for ventilating the target room RA.

The second outdoor-heat-exchanger inlet 92 c is located upstream from the outdoor heat exchanger 20, and the indoor air also passes through the outdoor heat exchanger 20, in addition to the outdoor air. This structure increases the heat exchange efficiency of the outdoor heat exchanger 20 more than when the outdoor air alone passes through the outdoor heat exchanger 20. This structure causes less energy loss than when the indoor air is discharged without passing through the outdoor heat exchanger 20.

In particular, in the heating operation in which the outdoor heat exchanger 20 operates as an evaporator and the indoor heat exchanger 10 operates as a condenser, the heated indoor air reduces frosting on the outdoor heat exchanger 20. Thus, the outdoor heat exchanger 20 can maintain the heat exchange efficiency although the outdoor air has relatively high humidity.

The indoor-heat-exchanger ventilation channel definer 91 and the outdoor-heat-exchanger ventilation channel definer 92 are isolated from each other by the machine storage definer 93 and the circuit-board storage definer 94 located between the definers 91 and 92. Thus, the second outdoor-heat-exchanger inlet 92 c is spaced more from the indoor-heat-exchanger outlet 91 b than the indoor-heat-exchanger inlet 91 a. In other words, the second outdoor-heat-exchanger inlet 92 c faces the interior of the target room RA at a position farther from the indoor-heat-exchanger outlet 91 b than the indoor-heat-exchanger inlet 91 a.

Although the indoor-heat-exchanger ventilation channel definer 91 and the outdoor-heat-exchanger ventilation channel definer 92 are a part of the common housing 90, this structure is less likely to form a short circuit, in which indoor air immediately after being discharged from the indoor-heat-exchanger outlet 91 b is taken in through the second outdoor-heat-exchanger inlet 92 c without being fully circulated in the target room RA.

The second outdoor-heat-exchanger inlet 92 c is open in one of the multiple outer surfaces of the housing 90 facing the interior of the target room RA. The outer surface with the second outdoor-heat-exchanger inlet 92 c extends in the direction crossing the outer surface in which the indoor-heat-exchanger outlet 91 b is open. The location of the second outdoor-heat-exchanger inlet 92 c also contributes to reducing the above short circuit.

Embodiment 2

The structure according to Embodiment 1 may also include means for adjusting the amount of indoor air drawn into the outdoor-heat-exchanger ventilation channel S2 through the second outdoor-heat-exchanger inlet 92 c. A specific example will be described below.

As shown in FIG. 3, an air conditioner ventilation device 200 according to the present embodiment also includes a damper 201 at the second outdoor-heat-exchanger inlet 92 c. The damper 201 can adjust the amount of indoor air flowing into the outdoor-heat-exchanger ventilation channel S2 through the second outdoor-heat-exchanger inlet 92 c.

More specifically, the damper 201 can fully open or fully close the second outdoor-heat-exchanger inlet 92 c and adjust the degree of opening. The degree of opening herein refers to the ratio of the area over which the indoor air is allowed to pass to the area of the opening of the second outdoor-heat-exchanger inlet 92 c.

The damper 201 is controlled by the controller 70. The controller 70 controls the degree of opening of the damper 201 in accordance with the operation of a user specifying the amount of ventilation per unit time, and controls to fully close the damper 201 during a period immediately after the compressor 31 starts operating. Fully closing the damper 201 and interrupting discharge of indoor air to the exterior space RB can immediately increase the comfort of the target room RA.

The air conditioner ventilation device 200 according to the present embodiment includes an indoor temperature sensor 202 and an outdoor temperature sensor 203. The indoor temperature sensor 202 detects the temperature of the indoor air. The outdoor temperature sensor 203 detects the temperature of the outdoor air. The indoor temperature sensor 202 is located to face the indoor-heat-exchanger inlet 91 a, and the outdoor temperature sensor 203 is located to face the first outdoor-heat-exchanger inlet 92 a. The controller 70 also controls the damper 201 based on the detection results of the indoor and outdoor temperature sensors 202 and 203.

More specifically, the controller 70 reduces the degree of opening of the damper 201 when the change in the detection result of the indoor temperature sensor 202, or more specifically, when the difference between the indoor temperatures exceeds a difference threshold predetermined as an allowable temperature change within which the comfort is maintained. Thus, the discharge of indoor air to the exterior space RB is restricted to avoid a rapid change in the indoor temperature.

The controller 70 increases the degree of opening of the damper 201 when the detected value of the outdoor temperature sensor 203 decreases below a predetermined lowest threshold that is a temperature at which frosting may occur, while the air conditioner 80 is heating the target room RA. This increases the amount of heated indoor air that passes through the outdoor heat exchanger 20 and can prevent frosting on the outdoor heat exchanger 20. The other effects are the same as in Embodiment 1.

Embodiment 3

In Embodiment 1, the first outdoor-heat-exchanger inlet 92 a and the second outdoor-heat-exchanger inlet 92 c are located at different positions, but the first outdoor-heat-exchanger inlet 92 a can also serve as the second outdoor-heat-exchanger inlet 92 c. A specific example will be described below.

As shown in FIG. 4, an air conditioner ventilation device 300 according to the present embodiment is the same as in Embodiment 1 in the outside-air intake duct D1, but differs from Embodiment 1 in the outside-air intake duct D1 having a through-hole 301.

An opening at a first end of the outside-air intake duct D1 faces the exterior space RB. An opening at a second end of the outside-air intake duct D1 is connected to the first outdoor-heat-exchanger inlet 92 a. The through-hole 301 is formed in a portion of the outside-air intake duct D1 facing the target room RA between the first end and the second end.

During the operation of the outdoor fan 50, outdoor air is drawn in through the opening at the first end of the outside-air intake duct D1, and concurrently, indoor air is drawn in through the through-hole 301. Thus, the outdoor air and the indoor air are fed into the outdoor-heat-exchanger ventilation channel S2 through the first outdoor-heat-exchanger inlet 92 a. Thus, the first outdoor-heat-exchanger inlet 92 a also serves as the second outdoor-heat-exchanger inlet 92 c shown in FIG. 1.

In the present embodiment, the outside-air intake duct D1 has the through-hole 301 through which indoor air is taken in. Thus, the through-hole 301 can be easily spaced more from the indoor-heat-exchanger outlet 91 b than the second outdoor-heat-exchanger inlet 92 c shown in FIG. 1. This structure according to the present embodiment thus is further less likely to form a short circuit of indoor air flowing from the indoor-heat-exchanger outlet 91 b to the outdoor-heat-exchanger ventilation channel S2 than the structure according to Embodiment 1.

The through-hole 301 may be formed at any location of the outside-air intake duct D1 facing the target room RA between the first end and the second end. Thus, the through-hole 301 may be formed at another location with an increased design freedom. The other effects are the same as in Embodiment 1.

Embodiment 4

The structure according to Embodiment 3 may additionally include means for adjusting the amount of indoor air drawn into the outdoor-heat-exchanger ventilation channel S2. A specific example will be described below.

As shown in FIG. 5, an air conditioner ventilation device 400 according to the present embodiment also includes a damper 401 at the through-hole 301 in the outside-air intake duct D1. The damper 401 can adjust the amount of indoor air drawn into the outdoor-heat-exchanger ventilation channel S2 through the through-hole 301.

In the present embodiment, the outdoor temperature sensor 203 is located around the opening at the first end of the outside-air intake duct D1. The controller 70 operates based on the detection results of the indoor and outdoor temperature sensors 202 and 203, as in Embodiment 2. The other effects are the same as in Embodiment 3.

Embodiment 5

In Embodiment 1, the outside-air intake duct D1 is connected to the first outdoor-heat-exchanger inlet 92 a, and the discharge duct D2 is connected to the outdoor-heat-exchanger outlet 92 b. However, the outside-air intake duct D1 and the discharge duct D2 may be eliminated when the first outdoor-heat-exchanger inlet 92 a and the outdoor-heat-exchanger outlet 92 b face the exterior space RB. A specific example will be described below.

As shown in FIG. 6, in the present embodiment, the housing 90 extends through the building wall WL that separates the target room RA from the exterior space RB. The present embodiment is the same as Embodiment 1 in that the indoor-heat-exchanger ventilation channel definer 91 is installed in a target space RA to be air-conditioned, and the indoor-heat-exchanger inlet 91 a and the indoor-heat-exchanger outlet 91 b face the target space RA.

The present embodiment differs from Embodiment 1 in that the outdoor-heat-exchanger ventilation channel definer 92 is installed in the exterior space RB. The first outdoor-heat-exchanger inlet 92 a and the outdoor-heat-exchanger outlet 92 b face the exterior space RB. This structure thus eliminates the outside-air intake duct D1 and the discharge duct D2 shown in FIG. 1.

However, an air conditioner ventilation device 500 according to the present embodiment includes an indoor-air intake duct D3 to take indoor air into the outdoor-heat-exchanger ventilation channel S2.

An opening at a first end of the indoor-air intake duct D3 faces the interior of the target room RA. An opening at a second end of the indoor-air intake duct D3 is connected to the second outdoor-heat-exchanger inlet 92 c. The indoor-air intake duct D3 guides indoor air from the target room RA to the outdoor-heat-exchanger ventilation channel S2 separated by the wall WL to ventilate the target room RA.

The opening at the first end of the indoor-air intake duct D3 faces the interior of the target room RA at a position farther from the indoor-heat-exchanger outlet 91 b than the indoor-heat-exchanger inlet 91 a. This structure is less likely to form a short circuit of indoor air flowing from the indoor-heat-exchanger outlet 91 b to the outdoor-heat-exchanger ventilation channel S2. The other effects are the same as in Embodiment 1.

Embodiment 6

The structure according to Embodiment 5 may also include means for adjusting the amount of indoor air drawn into the outdoor-heat-exchanger ventilation channel S2. A specific example will be described below.

As shown in FIG. 7, an air conditioner ventilation device 600 according to the present embodiment also includes a damper 601 at the opening at the first end of the indoor-air intake duct D3. The damper 601 can adjust the amount of indoor air drawn into the outdoor-heat-exchanger ventilation channel S2 from the target room RA.

In the present embodiment, the outdoor temperature sensor 203 is located around the first outdoor-heat-exchanger inlet 92 a in the outer surface of the outdoor-heat-exchanger ventilation channel definer 92. The controller 70 operates based on the detection results of the indoor and outdoor temperature sensors 202 and 203, as in Embodiment 2. The other effects are the same as in Embodiment 5.

Embodiment 7

As shown in FIGS. 6 and 7, in Embodiments 5 and 6, the indoor-air intake duct D3 is installed outside the housing 90 but may be installed inside the housing 90. A specific example will be described below.

As shown in FIG. 8, an air conditioner ventilation device 700 according to the present embodiment has an indoor-air intake duct D4 in the housing 90. The indoor-air intake duct D4 guides the indoor air from the target room RA to the outdoor-heat-exchanger ventilation channel S2 through the second outdoor-heat-exchanger inlet 92 c.

Inside the housing 90, the indoor-air intake duct D4 extends from the indoor-heat-exchanger inlet 91 a to the second outdoor-heat-exchanger inlet 92 c through a portion facing the indoor-heat-exchanger ventilation channel S1 and the machine storage S3.

More specifically, an opening at a first end of the indoor-air intake duct D4 faces the interior of the target room RA at the indoor-heat-exchanger inlet 91 a, and an opening at a second end of the indoor-air intake duct D4 is connected to the second outdoor-heat-exchanger inlet 92 c.

In the present embodiment, the indoor-heat-exchanger inlet 91 a serves as a portion that takes in indoor air for air-conditioning and also for ventilation. The portion of the air conditioner ventilation device 700 exposed to the target room RA has a simple external design to improve appearance.

To ventilate the target room RA, the indoor air may be filtered to remove dust before being taken into the outdoor-heat-exchanger ventilation channel S2 to reduce accumulation of dust in the target room RA to the inner surface of the outdoor-heat-exchanger ventilation channel S2, the outdoor heat exchanger 20, and the outdoor fan 50.

A filter installed in the indoor-heat-exchanger inlet 91 a according to the present embodiment can remove dust from the indoor air flowing into the indoor-heat-exchanger ventilation channel S1 and into the outdoor-heat-exchanger ventilation channel S2. A single filter can thus be used.

Embodiment 8

Each of the structures according to Embodiments 1 to 7 may also include means for adjusting the amount of outdoor air drawn into the outdoor-heat-exchanger ventilation channel S2 through the first outdoor-heat-exchanger inlet 92 a. A specific example will be described below.

As shown in FIG. 9, an air conditioner ventilation device 800 according to the present embodiment also includes a damper 801 at the first outdoor-heat-exchanger inlet 92 a. The damper 801 can adjust the amount of outdoor air drawn into the outdoor-heat-exchanger ventilation channel S2 from the exterior space RB.

While the target room RA is being heated, the controller 70 reduces the degree of opening of the damper 801 when determining that the outdoor heat exchanger 20 is likely to be frosted based on the detection result of the outdoor temperature sensor 203. This increases the ratio of indoor air in the indoor air and the outdoor air flowing into the outdoor-heat-exchanger ventilation channel S2 accordingly to reduce frosting on the outdoor heat exchanger 20.

The controller 70 controls the air conditioner 80 to simply ventilate the target room RA without air-conditioning the target room RA. This control will be described using a bathroom as the target room RA. In response to a user operation performed by a user leaving the target room RA that is a bathroom, after using the target room RA being air-conditioned, the controller 70 stops the compressor 31 and the indoor fan 40 and fully closes the damper 801 with the outdoor fan 50 operating.

Thus, the controller 70 can stop air-conditioning the target room RA that is a bathroom, and simply continues ventilating the target room RA. When the damper 801 is fully closed, the outdoor fan 50 can intensively circulate air simply for ventilating the target room RA. Thus, the target room RA can be ventilated immediately.

Although embodiments of the present disclosure have been described, the present disclosure is not limited to these embodiments. The embodiments may be modified in the following manner.

FIG. 1 shows the structure including the second outdoor-heat-exchanger inlet 92 c located upstream from the outdoor heat exchanger 20. However, the second outdoor-heat-exchanger inlet 92 c may be located downstream from the outdoor heat exchanger 20. In this case, the target room RA can be ventilated although outdoor air alone, instead of both outdoor air and indoor air, passes through the outdoor heat exchanger 20.

FIG. 1 shows the structure in which the housing 90 is installed in the target room RA, and the indoor-heat-exchanger inlet 91 a, the indoor-heat-exchanger outlet 91 b, and the second outdoor-heat-exchanger inlet 92 c are thus exposed to the target room RA. However, the housing 90 may be installed at any position. The housing 90 may be installed at a position different from the target room RA when the indoor-heat-exchanger inlet 91 a, the indoor-heat-exchanger outlet 91 b, and the second outdoor-heat-exchanger inlet 92 c are connected to the target room RA through ducts (not shown). In some embodiments, the indoor-heat-exchanger ventilation channel definer 91 may be separate from the outdoor-heat-exchanger ventilation channel definer 92.

FIG. 1 shows axial-flow fans used as examples of the indoor fan 40 and the outdoor fan 50, but the indoor fan 40 and the outdoor fan 50 may be of another type. Centrifugal fans, mixed flow fans, or cross flow fans may be used as the indoor fan 40 and the outdoor fan 50. The indoor fan 40 and the outdoor fan 50 may be different types of fan. The indoor fan 40 may be located upstream from the indoor heat exchanger 10, and the outdoor fan 50 may be located upstream from the outdoor heat exchanger 20. The expansion device 32 may be an electronic expansion valve.

FIGS. 4 and 5 show an example structure including the outside-air intake duct D1 having one through-hole 301. However, the outside-air intake duct D1 may have multiple through-holes 301. The damper 401 may be located at each of the multiple through-holes 301. The controller 70 may control all the dampers 401 to have the same degree of opening or may individually control the dampers 401 to have different degrees of opening.

FIGS. 6 and 7 show an example structure including the housing 90 that extends through the wall WL, serving as a partition that separates the target room RA from the exterior space RB. The partition may be a building ceiling. In other words, the housing 90 may be installed on a ceiling. In some embodiments, the housing 90 may be fixed to a window frame (not shown) that connects the target room RA to the exterior space RB. The indoor-heat-exchanger ventilation channel definer 91 may be installed in the target space RA, and the outdoor-heat-exchanger ventilation channel definer 92 may be installed in the exterior space RB.

FIG. 7 shows an example structure including the damper 601 at the opening of the indoor-air intake duct D3 facing the exterior space RA. However, the damper 601 may be installed either inside the indoor-air intake duct D3 or at the second outdoor-heat-exchanger inlet 92 c.

FIG. 8 shows an example structure including the indoor-air intake duct D4 open at the indoor-heat-exchanger inlet 91 a. However, the indoor-air intake duct D4 may be open in a portion upstream from the outdoor-heat-exchanger ventilation channel S2 when, during the operation of the indoor fan 40 and the outdoor fan 50, the atmospheric pressure in a portion of the outdoor-heat-exchanger ventilation channel S2 upstream from the outdoor heat exchanger 20 is lower than the atmospheric pressure in a portion of the indoor-heat-exchanger ventilation channel 51 upstream from the indoor heat exchanger 10.

The foregoing describes some example embodiments for explanatory purposes. Although the foregoing discussion has presented specific embodiments, persons skilled in the art will recognize that changes may be made in form and detail without departing from the broader spirit and scope of the invention. Accordingly, the specification and drawings are to be regarded in an illustrative rather than a restrictive sense. This detailed description, therefore, is not to be taken in a limiting sense, and the scope of the invention is defined only by the included claims, along with the full range of equivalents to which such claims are entitled.

This application claims the benefit of Japanese Patent Application No. 2018-070546, filed on Apr. 2, 2018, the entire disclosure of which is incorporated by reference herein.

INDUSTRIAL APPLICABILITY

The air conditioner ventilation device and the air conditioner ventilation method according to the present disclosure are usable for air-conditioning and ventilating a target room to be air-conditioned.

REFERENCE SIGNS LIST

-   10 Indoor heat exchanger -   20 Outdoor heat exchanger -   30 Cooperative system -   31 Compressor -   32 Expansion device -   33 Refrigerant pipe -   34 Four-way valve -   40 Indoor fan -   50 Outdoor fan -   60 Power circuit -   70 Controller -   80 Air conditioner -   90 Housing -   91 Indoor-heat-exchanger ventilation channel definer -   91 a Indoor-heat-exchanger inlet -   91 b Indoor-heat-exchanger outlet -   92 Outdoor-heat-exchanger ventilation channel definer -   92 a First outdoor-heat-exchanger inlet -   92 b Outdoor-heat-exchanger outlet -   92 c Second outdoor-heat-exchanger inlet -   93 Machine storage definer -   94 Circuit-board storage definer -   100 Air conditioner ventilation device -   200 Air conditioner ventilation device -   201 Damper -   202 Indoor temperature sensor -   203 Outdoor temperature sensor -   300 Air conditioner ventilation device -   301 Through-hole -   400 Air conditioner ventilation device -   401 Damper -   500 Air conditioner ventilation device -   600 Air conditioner ventilation device -   601 Damper -   700 Air conditioner ventilation device -   800 Air conditioner ventilation device -   801 Damper -   D1 Outside-air intake duct -   D2 Exhaust duct -   D3 Indoor-air intake duct -   D4 Indoor-air intake duct -   S1 Indoor-heat-exchanger ventilation channel -   S2 Outdoor-heat-exchanger ventilation channel -   S3 Machine storage -   S4 Circuit board storage -   RA Target room to be air-conditioned -   RB Exterior space -   WL Building wall 

1. An air conditioner ventilation device, comprising: an outdoor heat exchanger being operable as an evaporator to evaporate a refrigerant, an indoor heat exchanger being operable as a condenser to condense the refrigerant; a cooperative system to constitute, together with the indoor heat exchanger and the outdoor heat exchanger, a refrigeration cycle in which the refrigerant circulates; an indoor-heat-exchanger ventilation channel definer having an indoor-heat-exchanger inlet and an indoor-heat-exchanger outlet each connected to a target room to be air-conditioned, the indoor-heat-exchanger ventilation channel definer defining an indoor-heat-exchanger ventilation channel connecting the indoor-heat-exchanger inlet to the indoor-heat-exchanger outlet, the indoor heat exchanger being located in the indoor-heat-exchanger ventilation channel; an indoor fan located in the indoor-heat-exchanger ventilation channel, the indoor fan being configured to create an airflow in the indoor-heat-exchanger ventilation channel, the airflow including indoor air in the target room drawn through the indoor-heat-exchanger inlet, passing through the indoor heat exchanger, and discharged to the target room through the indoor-heat-exchanger outlet; an outdoor-heat-exchanger ventilation channel definer having a first outdoor-heat-exchanger inlet, an outdoor-heat-exchanger outlet, and a second outdoor-heat-exchanger inlet, the first outdoor-heat-exchanger inlet and the outdoor-heat-exchanger outlet each being connected to an exterior space isolated from the target room, the second outdoor-heat-exchanger inlet being connected to the target room, the outdoor-heat-exchanger ventilation channel definer defining an outdoor-heat-exchanger ventilation channel connecting the first outdoor-heat-exchanger inlet and the second outdoor-heat-exchanger inlet to the outdoor-heat-exchanger outlet, the outdoor heat exchanger being located in the outdoor-heat-exchanger ventilation channel; an outdoor fan located in the outdoor-heat-exchanger ventilation channel, the outdoor fan being configured to create an airflow in the outdoor-heat-exchanger ventilation channel, the airflow including outdoor air in the exterior space drawn through the first outdoor-heat-exchanger inlet and the indoor air in the target room drawn through the second outdoor-heat-exchanger inlet, the drawn outdoor air and the drawn indoor air passing through the outdoor heat exchanger, the outdoor air and the indoor air being discharged to the exterior space through the outdoor-heat-exchanger outlet; an outdoor temperature sensor to detect temperature of the outdoor air; a damper to adjust an amount of the indoor air flowing into the outdoor-heat-exchanger ventilation channel through the second outdoor-heat-exchanger inlet; and a controller to control the damper to increase the amount of the indoor air flowing into the outdoor-heat-exchanger ventilation channel through the second outdoor-heat exchanger inlet when a detection result of the outdoor temperature sensor decreases below a predetermined lowest threshold that is a temperature at which there is a possibility that frosting occurs. 2-3. (canceled)
 4. The air conditioner ventilation device according to claim 1, wherein the second outdoor-heat-exchanger inlet faces an interior of the target room at a position farther from the indoor-heat-exchanger outlet than the indoor-heat-exchanger inlet.
 5. (canceled)
 6. The air conditioner ventilation device according to claim 1, further comprising: an outside-air intake duct having an opening at a first end facing the exterior space, and an opening at a second end connected to the first outdoor-heat-exchanger inlet, wherein the outside-air intake duct has, in a portion facing the target room between the first end and the second end, a through-hole through which the indoor air is drawn in to allow the first outdoor-heat-exchanger inlet to serve as the second outdoor-heat-exchanger inlet, and the damper adjusts the amount of the indoor air flowing into the outside-air intake duct through the through-hole.
 7. (canceled)
 8. The air conditioner ventilation device according to claim 1, wherein the outdoor-heat-exchanger ventilation channel definer is located in the exterior space, and the first outdoor-heat-exchanger inlet and the outdoor-heat-exchanger outlet face the exterior space, the air conditioner ventilation device further comprises an indoor-air intake duct having an opening at a first end facing an interior of the target room, and an opening at a second end connected to the second outdoor-heat-exchanger inlet, and the damper adjusts the amount of the indoor air flowing into the indoor-air intake duct through the opening at the first end of the indoor-air intake duct.
 9. (canceled)
 10. An air conditioner ventilation method, comprising: performing, between indoor air and an indoor heat exchanger, indoor heat exchange including creating an airflow including the indoor air drawn in from a target room to be air-conditioned and causing the indoor air to pass through the indoor heat exchanger and to return to the target room while a refrigeration cycle in which a refrigerant circulate is constituted using the indoor heat exchanger and an outdoor heat exchanger, the outdoor heat exchanger being operable as an evaporator to evaporate the refrigerant, the indoor heat exchanger being operable as a condenser to condense the refrigerant; performing outdoor heat exchange and ventilation including drawing in outdoor air from an exterior space isolated from the target room and drawing in the indoor air from the target room, and causing the outside air and the indoor air drawn in to pass through the outdoor heat exchanger and to be discharged to the exterior space; and controlling the amount of the indoor air passing through the outdoor heat exchanger to increase the amount of the indoor air passing therethrough when a detection result of temperature of the outdoor air decreases below a predetermined lowest threshold that is a temperature at which there is a possibility that frosting occurs. 